1. Field of the Invention
The present invention generally relates to a vehicle communication system for direct communication between vehicles. More specifically, the present invention relates to a vehicle communication system that uses an omni-directional antenna and a bi-directional antenna to assist the driver obtain road information.
2. Background Information
Recently, vehicles are being equipped with a variety of informational systems such as navigation systems, Sirius and XM satellite radio systems, the so-called CLARUS weather information system, two-way satellite services, built-in cell phones, DVD players and the like. These systems are sometimes interconnected for increased functionality. Various informational systems have been proposed that use wireless communications between vehicles and between infrastructures, such as roadside units. These wireless communication systems have a wide range of applications ranging from crash avoidance to entertainment systems. Enabling these communication systems might be possible with varying costs and capabilities. Thus, the type of wireless communication systems to be used depends on the particular application. Some examples of wireless technologies that are currently available include digital cellular systems, Bluetooth systems, wireless LAN systems and dedicated short range communications (DSRC) systems.
Dedicated short range communications (DSRC) is an emerging technology that has been recently investigated for suitability in vehicles for a wide range of applications. Communications between vehicles and to/from infrastructure will enable a vast number of potential systems ranging from crash avoidance to Internet entertainment systems.
DSRC technology will allow vehicles to communicate directly with other vehicles and with roadside units to exchange a wide range of information. In the United States, DSRC technology will use a high frequency radio transmission (5.9 GHz) that offers the potential to effectively support wireless data communications between vehicles, and between vehicles, roadside units and other infrastructure. The important feature of DSRC technology is that the latency time between communications is very low compared to most other technologies that are currently available. Another important feature of DSRC technology is the capability of conducting both point-to-point wireless communications and broadcast wireless messages in a limited broadcast area.
Accordingly, DSRC technology can be used to provide various information between vehicles and to/from infrastructure, and from vehicle-to-vehicle, such as providing GPS location, vehicle speed and other vehicle Parameter Identifiers (PIDs) including engine speed, engine run time, engine coolant temperature, barometric pressure, etc. When communications are established from one vehicle to other vehicles in close proximity, this information would be communicated between the vehicles to provide the vehicles with a complete understanding of the vehicles in the broadcast area. This information then can be used by the vehicles for both vehicle safety applications and non-safety applications.
In vehicle safety applications, a “Common Message Set” (CMS) would mostly likely be developed in which a prescribed set of vehicle Parameter Identifiers (PIDs) are broadcast by each vehicle to give relevant kinematical and location information such as GPS location/vehicle position, vehicle speed, vehicle dimensions etc. Once a potential safety concern is determined to exist, a warning system in the vehicles would notify the driver of the potential safety concern so that the driver can take the appropriate action.
In non-safety applications, a DSRC vehicle on-board unit would most likely provide an encrypted User ID that would coordinate with a specific account on a service provider's look-up table. Once the vehicle on-board unit establishes a link to the service provider, the vehicle on-board unit can be provided with various services associated with the specific account such as point of interest notification, map update download, in-route hotel reservations, etc. through a roadside unit in close proximity that is linked to the service provider.
Currently, DSRC equipped vehicles use a single omni-directional antenna that covers a prescribed radius about the vehicle. In a multi-lane highway scenario, the DSRC interference and backend calculations could be enormous given the extreme amount of information that could eventually be communicated between vehicles. Thus, it is desirable to minimize the DSRC interference and backend calculations.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved vehicle communication system. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.